1. Field of the Invention
The present invention relates generally to vertical probe devices and more particularly, to a vertical probe device having a positioning film.
2. Description of the Related Art
Taiwan Patent No. M483427 discloses a vertical probe device which includes a probe seat composed of upper, middle and lower dies or upper and lower dies, a positioning film disposed between the upper and lower dies, and a plurality of probe needles. Each probe needle has a needle head penetrating through the upper die and the positioning film, a needle tail penetrating through the lower die, and a curved needle body located in an accommodating space defined between the upper and lower dies.
In the process of assembling the vertical probe device, the positioning film is fixedly disposed above the lower die in advance, then the probe needles are installed in a way that each probe needle penetrates through the positioning film and the lower die in order, and finally the upper die is fixedly disposed above the positioning film. The positioning film has a plurality of positioning holes corresponding in position to probe needle installation holes of the upper die, and the needle head of each probe needle is individually inserted through one of the positioning holes. Therefore, the needle heads can be positioned correspondingly to the probe needle installation holes of the upper die by the positioning film before the installation of the upper die, so that the needle heads will be inserted through the probe needle installation holes of the upper die smoothly while the upper die is installed.
It is obvious that if the size of the positioning holes is close to the size of the needle heads, the positioning film can limit the needle heads in desired positions very well, but the installation of the probe needles will become relatively more difficult, resulting in low efficiency of installing the probe needles and high possibility of deforming the probe needles. Besides, when the probe needle is deformed and needs to be replaced, such positioning film causes difficulty to the replacement of the probe needle, and the probe needle may even hook the positioning film while being removed to cause the positioning film to be lifted and flipped over. However, if the positioning holes are enlarged, the installation of the probe needles may become relatively easier, but the positions of the needle heads cannot be well limited, causing more difficulty to the installation of the upper die. When the upper die is not installed positively and smoothly, the probe needles may be liable to be damaged.
Furthermore, the needle bodies of some probe needles have narrow and long cross sections, such as that disclosed in the aforesaid Taiwan patent; in such condition, the positioning holes of the positioning film should be configured as irregular holes shaped correspondingly to both the needle head and the needle body. For example, the positioning hole may include a rectangular slot and a circular hole overlappingly located in the middle of the rectangular slot, as illustrated in FIG. 2 of Taiwan Patent No. I299790. Alternately, the positioning hole may be shaped as the other differently shaped positioning holes provided in the aforesaid patent. Such positioning film is relatively more difficult in manufacturing, and causes relatively more difficulty to the installation and the replacement of the probe needles.
Japan Patent Publication No. 2012-159368 discloses another vertical probe device, wherein the needle heads are positioned by upper and lower positioning films having the same configuration and piled on one another with an angular orientation difference of 90 degrees therebetween. Each of the positioning films has a plurality of elongated holes parallel to each other. In the process of installation of the probe needles, the needle heads of the probe needles are inserted through the elongated holes of the lower positioning film. After the installation of the probe needles to the lower positioning film is accomplished, the upper positioning film is disposed on the lower positioning film in a way that the needle heads are also inserted through the elongated holes of the upper positioning film, which are perpendicular to the elongated holes of the lower positioning film, and every two elongated holes perpendicular to each other form a square hole for positioning one of the needle heads.
The aforesaid installation of the probe needles can be performed relatively more easily because the probe needles are inserted through the elongated holes. Besides, even though the needle body has narrow and long cross sections, the positioning film without irregular holes can still be penetrated by such needle body. After the installations of the upper and lower positioning films are accomplished, the needle heads are positioned precisely, so that the upper die is easily installed. In practice, however, not all of the square holes formed by the upper and lower positioning films are needed to accommodate the needle heads. Therefore, when the needle heads penetrate through the lower positioning film but not yet penetrate through the upper positioning film, the elongated holes of the lower positioning film may have much unoccupied space. At this time, the needle heads are liable to deviate from the predetermined positions thereof quite distantly. In such condition, the deviating needle heads should be pulled back to the predetermined positions thereof during the installation of the upper positioning film, causing time-consumption to the installation of the upper positioning film.
U.S. Pat. No. 7,649,372 also discloses a vertical probe device having upper and lower positioning films, wherein the lower positioning film has through holes with relatively larger diameter to make the installation of the probe needles therethrough easier, and the upper positioning film has through holes with diameter very close to the external diameter of the needle head for positioning the needle heads. However, when the probe needles are to be crowdedly arranged together, the through holes of the lower positioning film should be arranged very close to each other. In such condition, the installation of the probe needles may become difficult and liable to have mistakes, and a very crowded arrangement of the probe needles is still unattainable.